1.
A bio-cultural approach to the study of food choice: The contribution of taste genetics, population and culture.
Risso, DS, Giuliani, C, Antinucci, M, Morini, G, Garagnani, P, Tofanelli, S, Luiselli, D
Appetite. 2017;:240-247
Abstract
The study of food choice, one of the most complex human traits, requires an integrated approach that takes into account environmental, socio-cultural and biological diversity. We recruited 183 volunteers from four geo-linguistic groups and highly diversified in terms of both genetic background and food habits from whom we collected genotypes and phenotypes tightly linked to taste perception. We confirmed previous genetic associations, in particular with stevioside perception, and noted significant differences in food consumption: in particular, broccoli, mustard and beer consumption scores were significantly higher (Adjusted P = 0.02, Adjusted P < 0.0001 and Adjusted P = 0.01, respectively) in North Europeans, when compared to the other groups. Licorice and Parmesan cheese showed lower consumption and liking scores in the Sri Lankan group (Adjusted P = 0.001 and Adjusted P < 0.001, respectively). We also highlighted how rs860170 (TAS2R16) strongly differentiated populations and was associated to salicin bitterness perception. Identifying genetic variants on chemosensory receptors that vary across populations and show associations with taste perception and food habits represents a step towards a better comprehension of this complex trait, aimed at improving the individual health status. This is the first study that concurrently explores the contribution of genetics, population diversity and cultural aspects in taste perception and food consumption.
2.
GPR40-induced insulin secretion by the novel agonist TAK-875: first clinical findings in patients with type 2 diabetes.
Araki, T, Hirayama, M, Hiroi, S, Kaku, K
Diabetes, obesity & metabolism. 2012;(3):271-8
Abstract
AIM: Free fatty acids act as signalling molecules for modulating insulin secretion, and their insulinotropic effects are glucose-dependent and mediated through G protein-coupled receptor 40 (GPR40). This mechanism is a potential target for new treatments for managing diabetes. In this study, we present the first clinical data for TAK-875, a novel highly selective, orally bioavailable GPR40 agonist, in Japanese patients with type 2 diabetes insufficiently controlled by diet or exercise therapy. METHODS This was an exploratory phase II, multicentre, randomized, double-blind, parallel group study comparing the efficacy and tolerability of TAK-875 100 and 400 mg, and placebo, all administered once daily for 2 weeks. RESULTS After 2 weeks of treatment, TAK-875 produced marked glucose lowering effects in a 75 g oral glucose tolerance test (OGTT) as evidenced by mean ± SE intergroup differences in plasma glucose AUC(0-3 h) of -12.98 ± 1.48 (p < 0.0001) and -8.12 ± 1.49 mmol·h/l (p < 0.0001), for TAK-875 400 mg vs. placebo and TAK-875 100 mg vs. placebo, respectively, and 2 h plasma glucose [-4.95 ± 0.71 (p < 0.0001) and -3.21 ± 0.71 mmol/l (p < 0.0001), respectively]. This was accompanied by a significant increase in insulin AUC(0-3 h) [34.68 ± 12.16 (p < 0.01) and 31.49 ± 12.20 (p < 0 · 05) µIU·h/ml, respectively]. Improvement in glycaemic profile was mirrored by a significant change in fasting plasma glucose [-2.37 ± 0·27 (p < 0.0001) and -1.88 ± 0.27 mmol/l (p < 0.0001), respectively]. No cases of hypoglycaemia were observed despite the significant reduction in plasma glucose. CONCLUSIONS These exploratory findings provide evidence of the glucose-dependent insulinotropic potential of the GPR40 agonist TAK-875, and the promising clinical changes support future longer term clinical investigation.
3.
G-Protein-coupled receptor-associated A-kinase anchoring proteins: AKAP79 and AKAP250 (gravin).
Wang, HY, Tao, J, Shumay, E, Malbon, CC
European journal of cell biology. 2006;(7):643-50
Abstract
A-kinase anchoring proteins (AKAPs) define an expanding group of scaffold proteins that display a signature binding site for the RI/RII subunit of protein kinase A. AKAPs are multivalent and a subset of these scaffold proteins also display the ability to associate with the prototypic member of G-protein-coupled receptors, the beta(2)-adrenergic receptor. Both AKAP79 (also known as AKAP5) and AKAP250 (also known as gravin or AKAP12) have been shown to associate with the beta(2)-adrenergic receptor, but each directs downstream signaling events in decidedly different manners. The primary structures, common and unique protein motifs are of interest. Both proteins display largely natively unfolded primary sequences that provide a necklace on which short, structured regions of sequence are found. Membrane association appears to involve both interactions with the lipid bilayer via docking to a G-protein-coupled receptor as well as interactions of short positively charged domains with the inner leaflet of the cell membrane. Gravin, unlike AKAP79, displays a canonical site at its N-terminus that is subject to N-myristoylation. AKAP79 appears to function in switching signaling pathways of the receptor from adenylylcyclase to activation of the mitogen-activated protein kinase cascade. Gravin, in contrast, is essential for the resensitization and recycling of the receptors following agonist-induced activation, desensitization, and internalization. Each AKAP provides a template that enables space-time continuum features to G-protein-coupled signaling pathways as well as a paradigm for explaining apparent compartmentalization of cell signaling.